The present invention relates to a digital audio signal player having a simulated analogue record, which is equipped with turnable control element for a DJ to turn to simulate an analogue record played being moved on the turntable by the DJ so that music is played with tone and speed being changed in accordance with the movement of the DJ's hands, more particularly the present invention provides a digital audio signal player having a simulated analogue record of the above mentioned nature that is not subject to magnetic interference of people and electronic equipments in the vicinity thereof.
In order to help increase lively and exciting atmosphere in a concert or a party such as is held in a PUB or a dancing hall, the DJ would make the music played with changing tone and speed by means of moving the analogue record on the turntable in various ways. When the DJ stops moving the record with his hands, the record will be played on the record player on a normal way immediately.
However, a single analogue has very limited capacity for storing music, therefore the DJ has to prepare a lot of records in each party that are likely to cause him inconvenience due to the large size and heavy weight.
In order to overcome the above disadvantages, the inventor of the present invention had disclosed a digital audio signal player having a simulated analogue record, which includes a driving IC 1, a CD driving motor 11, a turntable 12, an ejection motor 13, a laser pick-up 14, a laser pick-up moving motor 15, a microprocessor 2, a control panel 21, a high frequency amplifier 3, a CD digital processor 4, a digital audio signal processor 5, a dynamic RAM 51, a digital/analog converter 7, a turnable control element 6, a glitch detecting circuit 63 and a low pass filter 8.
The turntable 12 is provided for holding an analogue CD, and connected to the CD driving motor 11. The driving IC 1 is electrically connected to both the CD driving motor 11 and the ejection motor 13 for activating the same to turn the turntable 12 and to eject the turntable 12 for removal of the CD respectively.
When the microprocessor 2 is activated, the same will make the high frequency amplifier 3 send out laser light, and make the CD digital processor 4 activate the laser pick-up 14 by means of the driving IC 1. The driving IC 1 will also activate the laser pick-up moving motor 15 to move the laser pick-up 14. The laser pick-up 14 sends a signal to the CD digital processor 4 via the high frequency amplifier 3 such that the CD digital processor 4 can inform the microprocessor 2 whether the laser light has focused; if the laser light fails to focus, the microprocessor 2 will stop; if the laser light has focused successfully, the microprocessor 2 activates the CD digital processor 4 to make the CD driving motor 11 work via the driving IC 1 such that the analogue CD positioned on the turntable 12 is rotated at twice the normal speed. And, the laser pick-up 14 reads the data of the analogue CD, and sends the data to both the microprocessor 2 and the digital audio signal processor 5 via the high frequency amplifier 3 and the CD digital processor 4; the microprocessor 2 will also make the control panel 21 show information about the CD, the digital audio signal process 5 will store the data of the CD in the dynamic RAM 51. A control panel 21 is connected to the microprocessor 2 so that information about the CD can be shown.
The turnable control element 6 is made of conductive materials and has a round shape, and electrically connected to the digital audio signal processor 5. The control element 6 normally sends out original signal 61, and will send out an interfering signal 62, which is stronger than the signal 61, when the same is touched by a person's hand. A sensor (not shown) of the control element 6 will senses the rotating speed and direction of the control element 6. The interfering signal 62 will be processed by an interfering signal detecting circuit 63, and then sent to the microprocessor 2. The digital/analog converter 7 is electrically connected to both the digital audio signal processor 5 and the low pass filter 8. The microprocessor 2 can make comparison between the signal 61 and the interfering signal 62, and determine that a user has touched the control element 6 if the difference between the signal 61 and the interfering signal 62 exceeds a predetermined amount.
Thus, when a user such as a DJ rotates the turnable control element 6 with the hands, the digital audio signal processor 5 will process and sent out the data stored in the dynamic RAM 51 in a manner according to the movement of the control element 6 sensed by the sensor, i.e. the user can control the speed and tone of the data send out from the digital audio signal processor 5. Then, the data is converted into analogue ones by means of the digital/analog converter 7. And, the analogue data are processed by the low pass filter 8, and played as music. When the user stops touching or moving the control element 6, the interfering signal 62 will disappear immediately, and accordingly the microprocessor 2 and the digital audio signal processor 5 will begin to play the music in the normal way.
Although the above player with simulated analogue record can play music with changing tone and speed to help increase lively and exciting atmosphere when a DJ rotate the turnable control element to simulate a record being rotated by the hand, it is found to have a disadvantage that the interfering signal detecting circuit 63 will sense other magnetic interference that is produced by the crowd and various electronic equipments in a dancing hall, thus wrongly making music played with changing tone and speed when the DJ doesn't intend to.